In the rich text editor:
@MightyVash
In a comment:
[MightyVash](https://chowlings.com/user/MightyVash)
For Names and Avatars:
In the rich text editor:
%MightyVash
In a comment:
[![MightyVash's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/MightyVash) [MightyVash](https://chowlings.com/user/MightyVash)